Paper is a thin sheet of matted cellulose fibers. Largely derived from lignocellulose, paper is created from a pulp dissolved into a slurry that is drained and dried into sheets. Different types of paper are defined by constituent fiber, paper pulp, sizing, coating, paper size, paper density and grammage.
The papermaking process developed in East Asia at least as early as 105 CE by the Han court eunuch Cai Lun, although archaeological evidence exists of 2nd century BCE paper-like material in China. Before the industrialization of paper production, the most common paper was rag paper, made from discarded natural fiber textiles collected by ragpickers. The 1843 invention of wood pulp, coupled with the Second Industrial Revolution, made pulpwood paper the dominant variety to this day.
